Chemical compounds

ABSTRACT

Compound of formula (I) wherein: A is a bicyclic heteroaryl, optionally substituted with one or more substituents; B is linker group connecting group A to group D and comprising a 3 or 4 atom linker where each atom is independently selected from carbon, oxygen, nitrogen and sulphur and is optionally subsituted with one or more C 1-6  alkyl groups or two of such adjacent alkyl substituents may form a ring; C is aryl or a mono or bicyclic heteroaryl, each of which can be optionally substituted; D is an aryl or heteroaryl, both of which are optionally substituted R 1  is hydrogen, C 1-5  alkyl, C 1-3  alkanoyl or C 1-3  alkoxycarbonyl; R 2  to R 5  are each independently selected from hydrogen, C 1-6  alkyl, aryl and heteroaryl containing up to 2 heteroatoms chosen from oxygen, sulphur and nitrogen, the aryl and heteroaryl optionally substituted with C 1-6  alkyl, C 2-6  alkenyl, C 2-6  alkynyl, C 1-4  alkoxy, C 1-4  alkanoyl, C 1-6  alkylamino, C 1-4 alkylC 1-6 alkyoxyl, C 1-6 alkylaminoC 1-6 alkyl, nitro, cyano, halogeno, trifluoromethyl, hydroxy, (CH 2 ) p OH where p is 1 or 2, —CO 2 R a , and —CONR a R b , where R a  and R b  are independently selected from hydrogen and C 1-6  alkyl or two of R 2  to R 5  can be taken together to form a 3 to 7 membered ring; R 6  is an acidic functional group; r and s are each independently 0 or 1 with the proviso that r and s cannot both be 0; or a pharmaceutically acceptable salt or in vivo hydrolysable derivative thereof.

This application is the national phase of international applicationPCT/GB99/02342 filed Jul. 20, 1999 which designated the U.S., and thatinternational application was published under PCT Article 21 (2) inEnglish.

This invention relates to compounds which are inhibitors of theinteraction between the integrin α₄β₁, also known as Very Late Antigen-4(VLA-4) or CD49d/CD29, and its protein ligands, for example VascularCell Adhesion Molecule-1 (VCAM-1) and fibronectin. This inventionfurther relates to processes for preparing such compounds, topharmaceutical compositions containing them and to their use in methodsof therapeutic application.

α₄β₁ is a member of the integrin family of heterodimeric cell surfacereceptors that are composed of noncovalently associated glycoproteinsubunits (α and β) and are involved in cell adhesion to other cells orto extracellular matrix. There are at least 14 different human integrinα subunits and at least 8 different β subunits and each , subunit canform a heterodimer with one or more a subunits. Integrins can besubdivided based on their β subunit composition. α₄β₁ is one of severalβ₁ integrins, also known as Very Late Antigens (VLA).

The interactions between integrins and their protein ligands arefundamental for maintaining cell function, for example by tetheringcells at a particular location, facilitating cell migration, orproviding survival signals to cells from their environment. Ligandsrecognised by integrins include extracellular matrix proteins, such ascollagen and fibronectin; plasma proteins, such as fibrinogen; and cellsurface molecules, such as transmembrane proteins of the immunoglobulinsuperfamily and cell-bound complement. The specificity of theinteraction between integrin and ligand is governed by the α and βsubunit composition

Integrin α₄β₁ is expressed on numerous hematopoietic cells andestablished cell lines, including hematopoietic precursors, peripheraland cytotoxic T lymphocytes, B lymphocytes, monocytes, thymocytes andeosinophils [Hemler, M. E. et al (1987), J. Biol. Chem., 262,11478-11485; Bochner, B. S. et al (1991), J. Exp. Med., 173, 1553-1556].Unlike other β₁, integrins that bind only to cell-extracellular matrixproteins, α₄β₁ binds to VCAM-1, an immunoglobulin superfamily memberexpressed on the cell surface, for example on vascular endothelialcells, and to fibronectin containing the alternatively spliced type IIIconnecting segment (CS-1 fibronectin) [Elices, M. J. et al (1990), Cell,60, 577-584; Wayner, E. A. et al (1989). J. Cell Biol., 109, 1321-1330].

The activation and extravasation of blood leukocytes plays a major rolein the development and progression of inflammatory diseases. Celladhesion to the vascular endothelium is required before cells migratefrom the blood into inflamed tissue and is mediated by specificinteractions between cell adhesion molecules on the surface of vascularendothelial cells and circulating leukocytes [Sharar, S. R. et al(1995). Springer Semin. Immunopathol., 16, 359-378]. α₄β₁ is believed tohave an important role in the recruitment of lymphocytes, monocytes andeosinophils during inflammation. α₄β₁/ligand binding has also beenimplicated in T-cell proliferation, B-cell localisation to germinalcentres, haemopoeitic progenitor cell localisation in the bone marrow,placental development, muscle development and tumour cell metastasis.

The affinity of α₄β₁ for its ligands is normally low but chemokinesexpressed by inflamed vascular endothelium act via receptors on theleukocyte surface to upregulate α₄β₁ function [Weber, C. et al (1996),J. Cell Biol., 134, 1063-1073]. VCAM-1 expression is upregulated onendothelial cells in vitro by inflammatory cytokines [Osborn, L. et al(1989) Cell, 59, 1203-1211] and in human inflammatory diseases such asrheumatoid arthritis [Morales-Ducret, J. et al (1992). J. Immunol., 149,1424-1431], multiple sclerosis [Cannella, B. et al., (1995). Ann.Neurol., 37, 424-435), allergic asthma [Fukuda, T. et al (1996), Am. J.Respir. Cell Mol. Biol., 14, 84-94] and atherosclerosis [O'Brien, K. D.et al (1993). J. Clin. Invest., 92, 945-951].

Monoclonal antibodies directed against the α₄ integrin subunit have beenshown to be effective in a number of animal models of human inflammatorydiseases including multiple sclerosis, rheumatoid arthritis, allergicasthma, contact dermatitis, transplant rejection, insulin-dependentdiabetes, inflammatory bowel disease, and glomerulonephritis.

Integrins recognise short peptide motifs in their ligands The minimalα₄β₁ binding epitope in CS-1 is the tripeptide leucine-asparticacid-valine (Leu-Asp-Val) [Komoriya, A., et al (1991). J. Biol. Chem.,266, 15075-15079] while VCAM-1 contains the similar sequenceisoleucine-aspartic acid-serine [Clements, J. M., et al (1994). J. CellSci., 107, 2127-2135]. The 25-amino acid fibronectin fragment, CS-1peptide, which contains the Leu Asp-Val motif, is a competitiveinhibitor of α₄β₁ binding to VCAM-1 [Makarem, R., et al (1994). J. Biol.Chem., 269, 4005-4011]. Small molecule α₄β₁ inhibitors based on theLeu-Asp-Val sequence in CS-1 have been described, for example the linearmolecule phenylacetic acid-Leu-Asp-Phe-D-Pro-amide [Molossi, S. et al(1995). J. Clin. Invest., 95, 2601-2610] and the disulphide cyclicpeptide Cys-Trp-Leu-Asp-Val-Cys [Vanderslice, P., et al (1997). J.Immunol., 158, 1710-1718].

More recently, non- and semi-peptidic compounds which inhibit α₄β₁/VCAMbinding and which can be orally administered have been reported in forexample, WO96/22966 and WO98/04247.

There remains a continuing need for alternative compounds which inhibitthe interaction between VCAM-1 and fibronectin with integrin α₄β₁ and,in particular, for compounds which can be administered by an oral route.

We have now found a group of compounds which contain a bicyclicheteroaryl ring system which inhibit this interaction.

Accordingly the present invention provides a compound of formula (I)

wherein:

A is a bicyclic heteroaryl, optionally substituted with one or moresubstituents independently selected from C₁₋₆ alkyl, C₁₋₆ alkanoyl,C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆ alkoxy, C₁₋₆ alkylamino, C₁₋₆ alkylthio,C₁₋₄ alkylsulphonyl, C₁₋₄alkoxylC₁₋₆alkyl, C₁₋₆alkylamino-C₁₋₆alkyl,carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆alkynyloxy,di-[(C₁₋₆)alkyl]amino, C₂₋₆alkanoylamino, N—C₁₋₆alkylcarbamoyl,C₁₋₆alkoxylcarbonyl, halogeno, nitro, cyano, amino trifluoromethyl,trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a) and—CONR^(a)R^(b), where R^(a) and R^(b) are independently hydrogen or C₁₋₆alkyl, linked to the nitrogen via a ring carbon atom in one ring and tothe group B by a ring carbon atom in the second ring;

B is linker group connecting group A to group D and comprising a 3 or 4atom linker where each atom is independently selected from carbon,oxygen, nitrogen and sulphur and is optionally substituted with one ormore C₁₋₆ alkyl groups or two of such adjacent alkyl substituents mayform a ring;

C is aryl or a mono or bicyclic heteroaryl, each of which can beoptionally substituted with one or more substituents independentlyselected from C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆ alkoxy, C₁₋₄alkanoyl, C₁₋₆ alkylamino, C₁₋₆ alkylthio, C₁₋₄ alkylsulphonyl,C₁₋₄alkoxyl-C₁₋₆alkyl, C₁₋₆alkylaminoC₁₋₆alkyl, carboxy, carbamoyl, C₂₋₆alkenyloxy, C₂₋₆alkynyloxy, di-[(C₁₋₆)alkyl]amino, C₂₋₆alkanoylamino,N—C₁₋₆alkylcarbamoyl, C₁₋₆alkoxylcarbonyl, phenoxy, cyano, nitro, amino,halogeno, trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH wherep is 1 or 2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently hydrogen or C₁₋₆ alkyl, linked to NR¹ through a ringcarbon atom;

D is an aryl or heteroaryl, both of which are optionally substitutedwith one or more substituents independently selected from C₁₋₆ alkyl,C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino,C₁₋₆ alkylthio, C₁₋₄ alkylsulphonyl, C₁₋₄alkoxylC₁₋₄alkyl,C₁₋₆alkylaminoC₁₋₆alkyl, carboxy, carbamoyl, C₂₋₆ alkenyloxy,C₂₋₆alkynyloxy, di-[(C₁₋₆)alkyl]amino, C₂₋₆alkanoylamino,N—C₁₋₆alkylcarbamoyl, C₁₋₆alkoxylcarbonyl, phenoxy, cyano, nitro, amino,halogeno, trifluoromethyl, trifluoromethoxy, hydroxy, (CH)_(p)OH where pis 1 or 2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently hydrogen or C₁₋₆ alkyl;

R¹ is hydrogen, C₁₋₅ alkyl, C₁₋₃ alkanoyl or C₁₋₃ alkoxycarbonyl;

R² to R⁵ are each independently selected from hydrogen, C₁₋₆ alkyl, aryland heteroaryl containing up to 2 heteroatoms chosen from oxygen,sulphur and nitrogen, the aryl and heteroaryl optionally substitutedwith C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₄ alkoxy, C₁₋₄ alkanoyl,C₁₋₆ alkylamino, C₁₋₄alkylC₁₋₆alkyoxyl, C₁₋₆alkylaminoC₁₋₆alkyl, nitro,cyano, halogeno, trifluoromethyl, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a), and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently selected from hydrogen and C₁₋₆ alkyl or two of R² to R⁵can be taken together to form a 3 to 7 membered ring;

R⁶ is an acidic functional group;

r and s are each independently 0 or 1 with the proviso that r and scannot both be 0;

or a pharmaceutically acceptable salt or in vivo hydrolysable derivativethereof.

In this specification the following definitions are adopted:

‘Bicyclic heteroaryl’ means an aromatic 5,6- 6,5- or 6,6-fused ringsystem wherein one or both rings contain ring heteroatoms. The ringsystem may contain up to three heteroatoms, independently selected fromoxygen, nitrogen or sulphur and can be optionally substituted with oneor more substituents selected from C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl,C₁₋₆ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₄alkoxylC₁₋₆alkyl,C₁₋₆alkylaminoC₁₋₆alkyl, C₁₋₄ alkylsulphonyl, nitro, cyano, halogeno,trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a), and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently selected from hydrogen and C₁₋₆ alkyl. When the ringsystem contains more than one heteroatom at least one heteroatom isnitrogen. Examples of bicyclic heteroaryl's include quinazolinyl,benzothiophenyl, benzoxazolyl, benzimidazolyl, benzothiazolyl,benzofuranyl, indolyl, quinolinyl, phthalazinyl and benzotriazolyl.

‘Aryl’ typically means phenyl or naphthyl, preferably phenyl.

The 3 to 7 membered ring formed by the substituents R² to R⁵ and the 5to 7 membered ring formed by substituents R⁷, see below, can be an,optionally substituted, saturated or unsaturated ring, for examplephenyl and cyclohexane. However, the ring may contain up to threeheteroatoms independently selected from nitrogen, oxygen and sulphur.Examples of suitable ring systems include furanyl, pyrrolinyl,piperidinyl, piperazinyl, pyridyl, imidazolyl, thiazolyl, pyrazolyl,pyrimidinyl, triazinyl, pyridazinyl, pyrazinyl, morpholinyl,tetrahydrofuranyl, pyrrolidinyl, imidazolinyl, imidazolidinyl,pyrazolinyl, pyrazolidinyl, piperidinyl, dihydropyridinyl andtetrahydropyridinyl.

The term ‘acidic functional group’ means a group which incorporates anacidic hydrogen and includes carboxylic acids, tetrazoles, acylsulphonamides, sulphonic and sulphinic acids, and preferably is carboxy.

In this specification suitable specific groups for the substituentsmentioned include: for halogeno: fluoro, chloro, bromo and iodo forC₁₋₆alkyl (this includes straight chained, branched structures and ringsystems): methyl, ethyl, propyl, isopropyl, tert-butyl, cyclopropane andcyclohexane; for C₂₋₆alkenyl: vinyl, allyl and but-2-enyl; forC₁₋₆alkanoyl: formyl, acetyl, propionyl or butyryl; for C₂₋₆alkynyl:ethynyl, 2-propynyl and but-2-ynyl; for C₁₋₆alkoxy: methoxy, ethoxy,propoxy, isopropoxy and butoxy; for C₂₋₆alkenyloxy: vinyloxy andallyloxy; for C₂₋₄alkynyloxy: ethynyloxy and 2-propynyloxy; forC₁₋₆alkylamino: methylamino, ethylamino, propylamino, isopropylamino andbutylamino; for di-C₁₋₆alkylamino: dimethylarnino, diethylamino; forC₂₋₆alkanoylamino: acetamido, propionamido and butyramido; forN—C₁₋₆alkylcarbamoyl N-methylcarbamoyl, N-ethylcarbamoyl andN-propylcarbamoyl; for C₁₋₆alkoxycarbonyl: methoxycarbonyl,ethoxycarbonyl, propoxycarbonyl and tert-butoxycarbonyl; forC₁₋₄alkoxyC₁₋₆alkyl: methoxymethyl, ethoxymethyl, 1-methoxymethyl,2-methoxyethyl; for C₁₋₆ alkylthio: methylthio; for C₁₋₄ alkylsulphonyl:methylsulphonyl; for C₁₋₆alkylaminoC₁₋₆alkyl: —CH₂NHC₂H₅

It will be understood that B excludes those linker groups which areunstable in acid conditions such as those found in the stomach of ahuman or animal body such as

Suitably, B is selected from acetamido,

In one aspect of the invention, A is benzoxazolyl, optionallysubstituted as hereinbefore defined; B is selected from acetamnido,—C(R^(c)R^(d))—C(O)—NR^(e)—, where R^(c), R^(d) and R^(e) are eachindependently selected from hydrogen and C₁₋₂ alkyl, and—O—CH₂—C(O)—NH—, and most preferably is acetamido; C is phenyl,optionally substituted as hereinbefore defined; s, r and R¹ to R⁶ are ashereinbefore defined.

In a further aspect of the invention the compounds have the formula (II)

wherein

R¹ to R⁵, s and r are as hereinbefore defined;

each R⁷ is independently selected from C₁₋₆ alkyl, C₂₋₆alkenyl,C₂₋₆alkynyl, C₁₋₄ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino,C₁₋₄alkoxylC₁₋₆alkyl, C₁₋₆alkylaminoC₁₋₆alkyl, cyano, nitro, halogeno,trifluoromethyl, hydroxy, (CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a), and—CONR^(a)R^(b), where R^(a) and R^(b) are independently hydrogen or C₁₋₆alkyl, or two adjacent substituents can be taken together to form a 5-7membered ring;

R⁸ to R¹⁴ are independently selected from hydrogen, C₁₋₄ alkyl, C₁₋₄alkanoyl, C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₄ alkoxy, C₁₋₆alkylamino, C₁₋₄alkoxylC₁₋₆alkyl, C₁₋₆alkylaminoC₁₋₆alkyl, halogeno,nitro, cyano, trifluoromethyl, hydroxy, (CH₂)_(p)OH where p is 1 or 2,—CO₂R^(a), and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl;

m is zero or an integer from 1 to 5;

or a pharmaceutically acceptable salt or in vivo hydrolysable derivativethereof.

A particularly suitable class of compounds of formula (II) are thosewhere

R² and R³ are independently selected from hydrogen or C₁₋₆ alkyl;

R¹, R⁴ and R⁵ are each hydrogen;

R⁷ is independently selected from halogeno and C₁₋₆ alkyl, especiallymethyl;

R⁸, R⁹ to R¹¹ and R¹⁴ are each hydrogen;

R¹⁰ is hydrogen or methoxy;

R¹² is C₁₋₆ alkoxy, halogeno or hydrogen

s is zero, m is zero, 1 or 2, and r is 1

or a pharmaceutically acceptable salt or in vivo hydrolysable derivativethereof.

Particularly suitable compounds are those described in the examples.

Some compounds of formula (I) or (II) may possess chiral centres. It isto be understood that the invention encompasses all such optical isomersand diastereoisomers of formula (I) or (II) which inhibit theinteraction between VCAM-l and fibronectin with integrin α₄β₁.

The activities of the compounds of this invention to inhibit theinteraction between VCAM-1 and fibronectin with integrin α₄β₁ may bedetermined using a number of in vitro and in vivo screens.

For example, compounds of formula (I) or (II) preferably have an IC₅₀ of<10 μM, more preferably <1 μM in the MOLTA-4 cell/Fibronectin assayhereinafter described.

In order for it to be used, a compound of formula (I), (II) or apharmaceutically acceptable salt or an in vivo hydrolysable derivativethereof is typically formulated as a pharmaceutical composition inaccordance with standard pharmaceutical practice.

Thus, according to a further aspect of the invention there is provided apharmaceutical composition which comprises a compound of formula (I) or(II) or a pharmaceutically acceptable salt or an in vivo hydrolysablederivative thereof and a pharmaceutically acceptable carrier.

The pharmaceutical compositions of this invention may be in a formsuitable for oral use, for example a tablet, capsule, aqueous or oilysolution, suspension or emulsion; for nasal use, for example a snuff,nasal spray or nasal drops; for vaginal or rectal use, for example asuppository; for administration by inhalation, for example as a finelydivided powder or a liquid aerosol; for sub-lingual or buccal use, forexample a tablet or capsule; or for parenteral use (includingintravenous, subcutaneous, intramuscular, intravascular or infusion),for example a sterile aqueous or oily solution or suspension, or a depotformulation with drug incorporated in a biodegradable polymer. Thecomposition may be in a form suitable for topical administration such asfor example creams, ointments and gels. Skin patches are alsocontemplated. For these purposes, the compositions of this invention maybe formulated by means known in the art, such as for example, asdescribed in general terms, in Chapter 25.2 of Comprehensive MedicinalChemistry, Volume 5, Editor Hansch et al, Pergamon Press 1990.

Furthermore, the pharmaceutical composition of the present invention maycontain one or more additional pharmacological agents suitable fortreating one or more disease conditions referred to hereinabove inaddition to the compounds of the present invention. In a further aspect,the additional pharmacological agent or agents may be co-administered,either simultaneously or sequentially, with the pharmaceuticalcompositions of the invention.

The composition of the invention will normally be administered to humanssuch that the daily dose will be 0.01 to 75 mg/kg body weight andpreferably 0.1 to 15 mg/kg body weight. A preferred composition of theinvention is one suitable for oral administration in unit dosage formfor example a tablet or capsule which contains from 1 to 1000 mg andpreferably 10 to 500 mg of a compound according to the present inventionin each unit dose.

Thus, according to yet another aspect of the invention, there isprovided a compound of formula (I) or (II) or a pharmaceuticallyacceptable salt or an in vivo hydrolysable derivative thereof for use ina method of therapeutic treatment of the human or animal body.

In yet a further aspect of the invention the present invention providesa method of treating a disease mediated by the interaction betweenVCAM-1 and/or fibronectin and the integrin receptor α₄β₁ in need of suchtreatment which comprises administering to said warm-blooded mammals aneffective amount of a compound of formula (I) or (II) or apharmaceutically acceptable salt or an in vivo hydrolysable derivativethereof.

The present invention also provides the use of a compound of formula (I)or (II), a pharmaceutically acceptable salt or an in vivo hydrolysablederivative thereof in the production of a medicament for use in thetreatment of a disease or medical condition mediated by the interactionbetween fibronectin and/or VCAM-1 (especially VCAM-1) and the integrinreceptor α₄β₁;

In a preferred embodiment the mammal in need of treatment is sufferingfrom multiple sclerosis, rheumatoid arthritis, asthma, coronary arterydisease, psoriasis, atherosclerosis, transplant rejection, inflammatorybowel disease, insulin-dependent diabetes and glomerulonephritis.

In another aspect of the invention, there is provided a process forpreparing a compound of formula (I), a pharmaceutically acceptable saltor an in vivo hydrolysable derivative thereof which process comprisescoupling together, via the formation of an amide bond, a compound offormula (III)

where L is a leaving group,

and an appropriate amine, where any functional group is optionallyprotected;

and thereafter, if necessary:

a) removing any protecting group; and

b) forming a pharmaceutically acceptable salt or in vivo hydrolysablederivative.

A particular process for preparing compounds of formula (I) involvescoupling together a compound of formula (IV) where R¹ and A are ashereinbefore defined and T₁ is selected from CH₂CO₂H, OCH₂CO₂H and CO₂H,and a compound of formula (V) where R² to R⁵ are as hereinbefore definedand D has an unprotected CO₂H or NH₂ with the proviso that when T₁ isNH₂, D is an unprotected CO₂H and when T₁ is selected from CH₂CO₂H,OCH₂CO₂H, and CO₂H, D has an unprotected NH₂ and where any otherfunctional group is optionally protected; and thereafter, if necessary:

a) removing any protecting group; and

b) forming a pharmaceutically acceptable salt or in vivo hydrolysablederivative.

An example of a compound of formula (IV) where A is benzoxazole is acompound of formula (VI)

where R⁷, m, R⁸ to R¹⁰ are as hereinbefore defined, and T₃ is oxygen ora direct bond and T₄ is hydrogen. Compounds of formula (VI) can beprepared as follows starting with o-nitrophenols of the type (formula(VII) T₃=CH₂.CO₂Me) which can be prepared by a variety of methods whichinclude displacement of fluorine in compounds (formula (VII) T₃=F andwhere the hydroxyl is preferably protected) by diethyl sodiomalonatefollowed by hydrolysis and decarboxylation. Displacement of the fluorinein compounds of the type (formula (VIII); T₃=F, T₅=Bn) with hydroxideion gives phenols (formula (VIII) T₃=OH T₅=Bn) which can be reactedunder basic conditions with t-butylbromoacetate to give t-butylphenoxyacetates. ((formula (VIII) T₃=OCH₂CO.O^(t)Bu, T₅=Bn). The benrylprotecting group can be removed (e.g. Pd/H₂, Pd/ammonium formate orBBr₃) to yield a nitro phenol ((formula (VIII) T₃=OCH₂CO.O^(t)Bu, T₅=H).Alternatively, Pd mediated coupling with dimethyl malonate of compoundsof formula (VIII), (T₃=Br, T₅=Bn) gives compounds of formula (VIII)(T₃=CH₂CO₂Me, T₅=Bn). The benzyl group can be removed as described aboveto yield a nitro phenol (formula (VIII) T₃=CH₂CO₂Me, T₅=H).

Nitro phenols prepared as above can be reduced to an amino compound(formula (IX) T₃=oxygen or direct bond, T₄=Me or ^(t)Bu) using, forexample, Pd/H₂, Pd/ammonium formate or Fe/HOAc. The amino compounds areunstable and can be converted in situ into the corresponding alkyl2-phenylaminobenzoxazole-6-acetates (formula (VI) T₃=oxygen or directbond, T₄=Me. ^(t)Bu) using an appropriately

substituted phenyl isothiocyanate (X) or with an appropriatelysubstituted phenyl dithiocarbamate (XI) in the presence of mercuricoxide. Deprotection of these esters will yield the corresponding acids(formula (VI), T₄=H).

Compounds of formula (V) can be prepared as follows. Nitrophenols offormula (XII) where R¹¹, R¹³ to R¹⁴ are as hereinbefore defined on D andR¹⁵ is C₁₋₆ alkyl, especially methyl, may be alkylated by appropriatelysubstituted compounds of the formula (XIII) by methods which depend onthe nature of T₂. If T₂=OH the alkylation may be achieved by theMitsonobu procedure whereas if T₂=Br or I alkylation may be achieved by,for example, a base (K₂CO₃) in acetone or methyl ethyl ketone. Theresulting nitro compound may be reduced to the corresponding amine(formula (XIV)) (Pd/H₂, Pd/ammonium formate Fe/HOAc) which is an exampleof a compound of formula (V).

Compounds represented by formula (VI) (T₃=oxygen or direct bond, T₄=H)and by formula (XIV) may be coupled by the formation of an amide bond bya variety of methods commonly used in peptide synthesis to yield estersof compounds of formula 1. The reaction of a compound of formula (VI)with a compound of formula (XXV) is performed under standard couplingconditions for forming peptide bonds. They can be performed either on asolid support (Solid Phase Peptide Synthesis) or in solution usingnormal techniques used in the synthesis of organic compounds. With theexception of the solid support, all the other protecting groups,coupling agents, deblocking reagents and purification techniques aresimilar in both the solid phase and solution phase peptide synthesistechniques.

During the reaction, amino acid functional groups may, if necessary, beprotected by protecting groups, for example Boc (rt-butoxycarbonyl).Such groups can be cleaved when necessary using standard techniques suchas acid or base treatment.

Suitable protecting groups for the protection of the acid functionalgroups include esters.

Coupling reagents for forming peptide bonds include the commonly usedazide, symmetrical anhydride, mixed anhydride and various active estersand carbodiimides. In the case of carbodiimides, additives such as1-hydroxybenzotriazole and N-hydroxysuccinimide may also be added. Othercoupling reagents include1H-benzotriazole-1-yl-oxy-tris-pyrrolidinophosphoniumhexafluorophosphate (PBTU),(2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate(TBTU), (2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluroniumhexafluorophosphate (HBTU)] andO-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluroniumhexafluorophosphate (HATU).

The coupling reactions can be performed at temperatures between −20° C.to 40° C. The time of the reaction can vary such as between 10 minutesand 24 hours.

Suitable purification methods for the intermediates and final productsinclude chromatographic techniques such as high pressure liquidchromatography (HPLC) along with many other standard techniques used inorganic chemistry (e.g. solvent extraction and crystallisation).

Moieties which do not have an amide bond coupling (i.e. compounds offormula (I) in which B does not include an amide bond) may be coupled byone of several methods of which two are given below.

Starting with a compound of formula (XV) where R² to R⁶, are ashereinbefore defined and R¹¹, R¹³, R¹⁴, R¹⁶ and R¹⁷ representsubstituents on D as hereinbefore defined. A requirement of compounds offormula (XV) is that one of the groups of R¹¹, R¹³, R¹⁴, R¹⁶ and R¹⁷will be capable of providing all or part of the link B. When one ofthese groups is so chosen, the remaining groups must be chosen so thatthey do not impede or complicate the regiospecificity of the subsequentcoupling. Such a group may be bromo, iodo, formyl(—CHO), acyl (R.CO),haloalkyl (particularly halomethyl) and amino. In an example of acompound of formula (XV) where R¹⁷ Br, Pd mediated amination (Buchwald)with a protected cyclic amine such as (XVI) can give, after deprotectionof the hydroxyl group, compounds of the formula (XVII).

Coupling, for example under Mitsonubu conditions, of compounds offormula (XVII) with a phenol of formula (XVIII) where R⁷ and m are ashereinbefore defined (prepared, for example, by the reaction of athiocarbamate of formula (XIV) with, for example, 4-amino resorcinolhydrochloride and mediated by mercuric oxide) can give compoundsaccording to the invention, such as

In an example of a compound of formula (XV) where R¹⁷=formyl, couplingmay be achieved by reductive amination with a compound of formula (XX)T₇=an amino function

e.g. NH₂, CH₂NH₂ and R⁷, R¹¹ to R¹³ and m are as hereinbefore definedprovide compounds according to the invention.

It will be appreciated by those skilled in the art that it is possibleto incorporate other linker groups by adjusting the group T₇ and thegroup R¹⁷.

The invention is further limited by the following biological testmethods, data and non-limiting examples.

EXAMPLES Example 1 Preparation of4-(5-{[2-(2-Anilino-1,3-benzoxazol-6-yl)acetyl]amino}-2-methoxyphenoxy)-3-methylbutanoicAcid

Methyl-4-{5-[2-(2-anilino-1,3-benzoxazol-6-yl)-acetylamino]-2-methoxyphenoxy}-3-methyl-butanoate(0.07g) was treated in dimethylsulphoxide (1 ml) with 2M sodium hydroxide(0.5 ml) and stirred for 0.5 hr. The resulting mixture was thenacidified with acetic acid and diluted with water. The precipitatedproduct was filtered and washed with water to give the acid (0.05 g)

1H nmr (DMSO d6): 1.0d (d) 3H; 2.1-2.5d, (m), 3H; 3.65d, (s), 2H; 3.7d,(s), 3H; 3.75d, (m), 2H; 6.85d, (d), 1H; 7.0d, (t), 1H; 7.1d, (d). 1H;7.15d (d), 1H; 7.35d, (m) 6H; 7.7d, (d), 2H; 10.0d, (s), 1H; and 10.58d,(bs), 1H. Mass spectrum: M+H at 490.

a) Preparation of 2-(Benzyloxy)-4-fluoro-nitrobenzene

To 2-nitro-5-fluorophenol (6.28 g) in acetonitrile (50 ml) was addedpotassium carbonate (5.6 g) and benzyl bromide (7.2 g). The mixture wasstirred at reflux for 2 hrs, added to water and extracted with diethylether. The organic layer was washed with brine, dried and evaporated todryness to give 2-(benzyloxy)-4-fluoro-nitrobenzene (10.2 g) as a solid.nmr (deuterochloroform): 5.2d (s), 2H; 6.7d, (m), 1H; 6.8d (q), 1H; 7.4d(m), 5H; 8.0d, (q), 1H;

b) Preparation of Dimethyl-(3-benzyloxy-4-nitrophenyl)malonate

To dimethylmalonate (6.6 g) in N-methylpyrrolidone (30 ml) was added, inportions, sodium hydride (60% dispersion, 2 g) and the mixture stirreduntil all evolution of hydrogen had ceased.2-(benzyloxy)-4-fluoro-nitrobenzene (7.51 g) was then added and themixture heated at 80° C. for 4 hrs., cooled, added to water, acidifiedwith 2M hydrochloric acid and extracted with ethyl acetate (2 times).The organic extracts were combined, washed with water, brine, dried andevaporated to dryness. The residue was triturated with diethyl ether andfiltered to give dimethyl-(3-benzyloxy-4-nitrophenyl)malonate (6.6 g).

nmr (deuterochloroform): 3.75d, (s), 6H; 4.6d, (s), 1H; 5.25d, (s), 2H;7.05d, (q), 1H; 7.4d, (m), 6H; 7.8d, (d), 2H.

c) Preparation of 3-Hydroxy-4-nitrophenylacetic Acid

The malonic ester from step b) (3 g) was heated at 100° C. in a mixtureof acetic acid (20 ml) and conc. hydrochloric acid (10 ml) for 2 hrs.and then evaporated to dryness. The residue was triturated with amixture of diethyl ether and hexane to give3-hydroxy-4-nitrophenylacetic acid as a yellow solid (1.4 g) isolated byfiltration.

nmr (DMSOd6): 3.6d, (s), 2H; 6.8d, (d), 1H; 7.0d, (s), 1H; 7.8d, (d),1H; 10.5d, (bs), 1H; 12.8d, (bs), 1H.

d) Preparation of Methyl 3-hydroxy-4-nitrophenylacetate

3-hydroxy-4nitrophenylacetic acid (1.1 g) was refluxed in methanol (20ml) containing 0.5 ml of conc. sulphuric acid for 4 hrs., diluted withwater and extracted with diethyl ether. The organic layer was separated,washed with aqueous sodium bicarbonate, brine, dried and then evaporatedto dryness to give methyl 3-hydroxy-4-nitrophenylacetate (1.2 g) as agum which crystallised on standing.

Nmr (deuterochloroform): 3.65d, (s), 2H; 3.7d, (s), 3H; 6.9d, (q), 1H;7.1d, (d), 1H; 8.05d, (d), 1H; 10.6d, (s), 1H.

e) Preparation of Methyl 2-Phenylaminobenzoxazole-6-acetate

To methyl 3-hydroxy-4-nitrophenylacetate (0.58 g) in ethanol (10 ml) wasadded 0.1 g of 10% palladium/carbon catalyst and the mixture stirredunder an atmosphere of hydrogen for 1 hr. and the catalyst then removedby filtration. To the filtrate was added phenylisothiocyanate (0.41 g)and the mixture allowed to stand for 1 hr., and then yellow mercuricoxide (1 g) added and the solution stirred at reflux for 3 hrs., cooled,filtered and evaporated to dryness. The residue was purified bychromatography on silica using an increasingly polar mixture of ethylacetate/hexane and the appropriate fraction yielded methyl2-phenylaminobenzoxazole-6-acetate as a white solid (0.6 g).

nmr (deuterochloroform): ˜3.7d, (s), 2H; ˜3.7d, (s), 3H (distinctsinglets but very close); 7.1d, (m), 2H; 7.4d, (m), 4H; 7.3d, (s), 1H;7.6d, (d), 2H.

f) Preparation of 2-phenylaminobenzoxazole-6-acetic acid

To methyl 2-phenylaminobenzoxazole-6-acetate (0.28 g) in a mixture ofdimethyl sulphoxide (1 ml) and tetrahydrofuran (1 ml) was added 2Msodium hydroxide (1 ml). The mixture was stirred for 2 hrs. thenacidified with acetic acid and diluted with water and the precipitatefiltered and washed with water and dried to give2-phenylaminobenzoxazole-6-acetic acid (0.24 g) as a white solid.

nmr (DMSOd6): 3.6d, (s), 2H; 7.0d, (t), 1H; 7.1d, (d), 1H; 7.3d (m), 4H;7.75d, (d), 2H; 10.55d, (b s), 1H.

g) Preparation ofMethyl-4-{5-[2-(2-anilino-1,3-benzoxazol6-yl)-acetylamino]-2-methoxyphenoxy}-3-methyl-butanoate

To a mixture of 2-phenylaminobenzoxazole-6-acetic acid(0.067 g), methyl2-methyl-3-(2-methoxy-5-aminophenoxy)butyrate(0.057 g),hydroxybenzotriazole (0.067 g), and N-methylmorpholine(0.05 ml) indimethylformamide(0.25 ml) was added1-(3-dimethylaminopropyl)3-ethylcarbodiimide hydrochloride(0.095 g). Theresultant mixture was stirred for 48 hrs then added to water andextracted with ethyl acetate. The organic layer was separated, washedwith aqueous acetic acid, brine, aqueous sodium bicarbonate (2 times),dried and evaporated to dryness. The residue was purified by purified bychromatography on silica using an increasingly polar mixture of ethylacetateldichloromethane and the appropriate fraction yielded, afterevaporation to dryness, a solid which was triturated with a mixture ofdiethylether/hexane to give the product (0.08 g) as a purple-pink solid.

¹H nmr (DMSOd6/Acetic d4): 1.0d, (d), 3H; 2.1-2.5d, (m), 3H; 3.5d (s),3H; 3.65d, (s), 2H; 3.7d, (s), 3H; 3.75d, (m), 2H; 6.85d, (d), 1H; 7.0d,(t), 1H; 7.1d, (d), 1H; 7.15d (d), 1H; 7.35d, (m), 4H; 7.4d, (s), 1H;7.7d, (d), 2H.

Example 2 Preparation of4-[5-({2-[2-(3-Fluoroanilino)-1,3-benzoxazol-6-yl]acetyl}amino]-2-methoxyphenoxy}-3-methylbutanoicAcid

This was prepared by hydrolysis of the methyl ester from 2a) using theprocess described in Example 1

1H nmr (DMSO d6): 1.0d (d) 3H; 2.1-2.6d, (m), 3H; 3.6-3.8d, (m), 7H;6.75-6.9d(m)2H; 7.05d, (d), 1H; 7.1d, (d), 1H; 7.3-7.5d, (m) 5H; 7.75d,(d), 1H; 10.0d, (s), 1H; and 10.85d, (bs), 1H. m/e508 (MH)⁺.

a) Preparation of Methyl4-[5-({2-[2-(3-Fluoroanilino)-1,3-benzoxazol-6-yl]acetyl}amino]-2-methoxyphenoxy}-3-methylbutanoate

This was prepared {through the intermediatesmethyl-2-(3-fluorophenylamino) benzoxazole-6-acetate[m/e301, (MH)⁺]and2-(3-fluorophenylamino)benzoxazole-6-acetic acid[m/e287, (MH)⁺] }by theseries of processes described in Example 1e) to 1 g) using3-fluorophenyl isothiocyanate in place of phenyl isothiocyanate in stepe)

1H nmr (DMSO d6): 1.0d (d) 3H; 2.2-2.6d, (m), 3H; 3.6d, (s), 3H;3.65-3.8d, (m), 7H; 6.75-6.9d(m)2H; 7.05d, (d), 1H; 7.1d, (d), 1H;7.3-7.5d, (m) 5H; 7.75d, (d), 1H; 10.0d, (s), 1H; and 10.84d, (bs), 1H.m/e522 (MH)⁺.

Example 3 Preparation of4-(3-{[2-(2-Anilino-1,3-benzoxazol-6-yl)acetyl]amino}phenoxy)butanoicAcid

This was prepared by hydrolysis of the methyl ester from 3a using theprocess described in Example 1.

1H nmr (DMSO d6): 1.9d, (m), 2H; 2.3d, (t), 2H; 3.7d, (s), 2H; 3.9d,(m), 2H; 6.8d, (d), 1H; 7.0d, (t), 1H; 7.1d, (m), 3H; 7.3d (m), 4H;7.45d, (s) 1H; 7.75d, (d), 2H; 10.1d, (bs), 1H; and 10.55d, (bs), 1H.m/e444 (MH)⁻.

a) Preparation of Methyl4-(3-{[2-(2-Anilino-1,3-benzoxazol-6-yl)acetyl]amino}phenoxy)butanoate

This was prepared by the process described in Example 1 g) but usingmethyl-3-aminophenoxybutyrate as the amino component in the couplingreaction.

1H nmr (DMSO d6): 1.9d, (m), 2H; 2.4d, (t), 2H; 3.6d, (s), 3H; 3.7d,(s), 2H; 3.95d, (t), 2H; 6.6d, (d), 1H; 7.0d, (t), 1H; 7.05-7,2d, (m),3H; 7.3d (m), 4H; 7.45d, (s) 1H; 7.75d, (d), 2H; 10.1d, (bs), 1H; and10.55d, (bs), 1H. m/e460 (ME)⁺

Example 4 Preparation of4-[2-Methoxy-5-({2-[2-(2-toluidino)-1,3-benzoxazol-6-yl]acetyl}amino)-phenoxy]butanoicAcid

This was prepared by hydrolysis of the methyl ester from 4a using theprocess described in Example 1

1H nmr (DMSO d6): 1.0d (d) 3H; 2.1-2.6d, (m), 6H; 3.6-3.8d,(m), 7H;6.85d(m)1H; 7.0-7.3d, (m) 7H; 7.4d,(s),1H; 7.8 d, (d),1H; 9.6d, (bs),1H; 10.0d,(s), 1H. m/e504 (MH)⁺.

a) Preparation of Methyl4-[2-Methoxy-5-({2-[2-(2-toluidino)-1,3-benzoxazol-6-yl]acetyl}amino)-phenoxy]butanoate

This was prepared {through the intermediatesmethyl-2-(2-methylphenylamino) benzoxazole-6-acetate[m/e297, (MH)⁺]and2-(2-methylphenylamino)benzoxazole-6-acetic acid[m/e283, (MH)⁺]} by theseries of processes described in Example 1e) to 1 g) using2-methylphenyl isothiocyanate in place of phenyl isothiocyanate in stepe)

1H nmr (DMSO d6): 1.0d (d) 3H; 2.2-2.6d, (m),6H; 3.65-3.8d, (m),10H;6.85d(d)1H; 7.0-7.3d, (m), 7H; 7.4d,(s),1H; 7.8d, (d), 1H; 9.6d,(s), 1H; 10.0d, (s), 1H. m/e518 (MH)⁺.

Example 5 Preparation of4-(3-{[2-(2-Anilino-1,3-benzoxazol-5-yl)acetyl]amino}phenoxy)butanoicAcid

This was prepared by hydrolysis of the methyl ester using the processdescribed in Example 1.

1H nmr (DMSO d6): 1.9d, (m), 2H; 2.3d, (t), 2H; 3.7d, (s), 2H; 3.9d,(m), 2H; 6.6(d), 1H; 7.0-7.25d, (m), 4H; 7.3-7.5d (m), 5H; 7.7d, (d),2H; 10.1d, (bs), 1H; and 10.55d, (bs), 1H. m/e444 (MH)⁺.

a) Preparation of Methyl4-(3-{[2-(2-Anilino-1,3-benzoxazol-5-yl)acetyl]amino}phenoxy)butanoate

The series of processes described in Example 1d) to 1f) was repeatedusing 4-hydroxy-3-nitrophenylacetic acid in place of3-hydroxy-4-nitrophenylacetic acid to give the followingintermediates:Methyl 4-hydroxy-3-nitrophenylacetate; m/e210(MH)⁻. Methyl2-phenylaminobenzoxazole-5-acetate; m/e283(MH)⁺2-Phenylaminobenzoxazole-5-acetic acid; m/e267 (MH)⁻.

The process described in Example 1 g) was repeated using2-Phenylaminobenzoxazole-5-acetic acid as the acid andmethyl-3-aminophenoxybutyrate as the amino component in the couplingreaction to give methyl4-(3-{[2-(2-anilino-1,3-benzoxazol-5-yl)acetyl]amino}phenoxy) butanoateas a white solid:

1H nmr (DMSO d6): 1.9d, (m), 2H; 2.45d, (t), 2H; 3.6d, (s), 3H; 3.7d,(s), 2H; 3.95d, (t), 2H; 6.6d, (d), 1H; 6.9-7.2d, (m), 4H; 7.25-7,45d,(m), 5H; 7.75d, (d), 2H; 10.1d, (s), 1H; and 10.65d, (s), 1H. m/e460(MH)⁺.

Example 6 Preparation of2-Anilino-6-(3-[2-methyl-3-carboxypropoxy)-4-methoxy-anilinocarbonylmethoxy)benzoxazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1

1H NMR (DMSOd6): 1.0(d), 3H; 2.1-2.5, (m), 3H; 3.65-3.85(m), 5H;3.95(s), 3H; 4.7(s), 2H; 6.7, (d). 1H; 6.85-6.95(m), 2H; 7.0, (t),1H7.2(d), 1H; 7.3-7.4, (m), 3H; 7.7(d), 2H; 9.85, (s) 1H; 10.4(s), 1H;12.1, (brs), 1H. M-H 534.

a) Preparation of 5-Fluoro-3-methoxy-2-nitrophenol

A mixture of 3,5-difluoro-2-nitroanisole(4.36 g), dimethylsulphoxide(10mL) and 10N aqueous sodium hydroxide(6.5 mL) was stirred at ambienttemperature for 18 h and then at 60° C. for 3 h. The mixture was dilutedwith water and acidified with concentrated hydrochloric acid, extractedwith ethyl acetate and the extract was washed with water dried andevaporated to dryness. The residue was purified by flash chromatographyeluting with increasingly polar mixtures of ethyl acetate and hexane togive the product (3.0 g),(m/e 186, MH−).

b) Preparation of 3-Benzyloxy-5-fluoro-2-nitroanisole

A mixture of 5-fluoro-3-methoxy-2-nitrophenol(0.56 g), acetonitrile(5mL), potassium carbonate(0.46 g) and benzyl bromide(0.56 g) was stirredat reflux for 2 h. The cooled mixture was treated with water and ethylacetate and the organic phase was separated, washed with brine, driedand evaporated to dryness. The residue was purified by flashchromatography eluting with increasingly polar mixtures of ethyl acetateand hexane to give the product (0.82 g), (m/e278, MH+).

c) Preparation of 3-Benzyloxy-5-methoxy-4-nitrophenol

A mixture of 3-benzyloxy-5-fluoro-2-nitroanisole(0.75 g),dimethylsulphoxide(5 mL) and 5N aqueous sodium hydroxide(2 mL) wasstirred at 70° C. for 3 h. The mixture was diluted with water andacidified with concentrated hydrochloric acid, extracted with ethylacetate and the extract was washed with water dried and evaporated todryness to give the product (0.71 g), (m/e274, MH−).

d) Preparation of Methyl 3-Benzyloxy-5-methoxy4-nitrophenoxyacetate

A mixture of 3-benzyloxy-5-methoxy-4-nitrophenol(3.85 g), N,N-dimethylformamide (20 mL), potassium carbonate(2.8 g) and methylbromoacetate(2.42 g) was stirred at ambient temperature for 3 h. Themixture was treated with water and ethyl acetate and the organic phasewas separated, washed with brine, dried and evaporated to dryness. Theresidue was purified by flash chromatography eluting with increasinglypolar mixtures of ethyl acetate and hexane to give the product (4.6 g),(m/e348, MH+).

e) Preparation of 2-Anilino4-methoxy-6-methoxycarbonylmethoxybenzoxazole

A mixture of methyl 3-benzyloxy-5-methoxy4-nitrophenoxyacetate(1 g),ethanol(30 mL) and 10% palladium on carbon catalyst(0.2 g) was stirredstirred under an atmosphere of hydrogen for 18 h. The mixture wasfiltered and the filtrate treated with phenylisothiocyanate(0.35 mL)followed by yellow mercuric oxide(0.85 g). The mixture was stirred atreflux for 4 h, then filtered and the filtrate was evaporated todryness. The residue was purified by flash chromatography eluting withincreasingly polar mixtures of ethyl acetate and hexane to give theproduct (0.75 g),[m/e329MH+].

f) Preparation of 2-Anilino-4-methoxy-6-carboxymethoxybenzoxazole

2-Anilino4-methoxy-6-methoxycarbonylmethoxybenzoxazole was hydrolysed bythe process described in example to give2-anilino4-methoxy-6-carboxymethoxybenzoxazole [m/e315, MH+].

g) Preparation of methyl 3-methylglutarate

3-Methylglutaric anhydride (50 g; 390 mmol) and dry methanol (15.8 mL;390 mmol) were heated to reflux (≈100° C.). After 1 h the mixturestopped refluxing but was maintain at 100° C. overnight. After cooling,the mixture was distilled (≈95° C. at 0.2 mmHg) to give methyl3-methylglutarate (37 g, 59%) as a colourless oil.

MS (ES−) 159.0 (M-H)⁻. (ES+) 161.0 (M+H)⁺.

¹H NMR (300 MHz; CDCl₃) 1.10 (3H, d), 2.30 (2H, m), 2.45 (3H, m), 3.70(3H, s).

h) Preparation of (±) methyl 4-bromo-3-methylbutyrate

Methyl 3-methylglutarate(37 g; 231 mmol) was added to 1M NaOH (231 mL;231 mmol) causing the solution to warm slightly. This solution was addedto a solution of silver nitrate (39.2 g; 231 mmol) in water (184 mL) at60° C. A fine white precipitate formed immediately. The mixture wascooled and stirred in an ice bath for 1 h before being filtered, washedwith water, acetone and ether and partially dried on the filter. Thesolid was then dried over night at 80° C. in a vacuum oven to give thesilver salt of the methyl 3-methylglutarate(49 g, 79%) as a pale brownsolid. The silver salt of the methyl 3-methylglutarate (49 g; 184 mmol)was suspended in carbon tetrachloride (245 mL) and bromine (9.5 mL)slowly added. The reaction mixture warmed to ≈30° C. during this processand effervescence was seen. The reaction mixture was maintained at thistemperature by the rate of addition of bromine. After the final additionof bromine the viscous mixture was stirred for 0.5 h before being heatedat reflux for 1 h. After cooling, the pale yellow precipitate wasremoved by filtration and the filtrate washed with 1M aqueous sodiumthiosulphate, brine, dried (phase separation paper) and concentratedunder reduced pressure. This gave a pale yellow oil which contained 15%of methyl 3-methylglutarate as an impurity by ¹H NMR. This was removedby taking the oil up in dichloromethane (DCM) and washing with 1M NaOH.Drying and concentration as above gave (±) methyl4-bromo-3-methylbutyrate (25 g, 70%) as a pale yellow oil.

i) Preparation of Methyl 3-Methyl-4-(2-methoxy-5-nitrophenoxy)butyrate

A mixture of 2-methoxy-4-nitrophenol (0.207 mg. 1.23 mmole) {Aldrich},methyl 4-bromo-3-methylbutyrate(0.25 g. 1.35 mmole) and potassiumcarbonate (0.19 g. 1.35 mmole) in DMF (10 mL.) was heated and stirred at80° C. for 8 hours. After cooling, the inorganics were filtered off, andthe filtrate evaporated to dryness. The residue was dissolved indichloromethane and washed twice with water. After drying (MgSO₄) thesolvent was evaporated off to yield an oil. The oil was purified bychromatography (Varian Megabondelut silica column) using a gradient of100% dichloromethane to 20% ethyl acetate/dichloromethane to give methyl3-methyl-4-(2-methoxy-5-nitrophenoxy)butyrate as an oil (90 mg. 29%) ms284(M+)

j) Preparation of Methyl 3-Methyl-4-(2-methoxy-5-aminophenoxy)butyrate

At ambient temperature a rapidly stirred solution of methyl3-methyl-4-(2-methoxy-5-nitrophenoxy)butyrate(400 mg) in methanol (20mL) containing 10% palladium on carbon (40 mg) was exposed to anatmosphere of hydrogen. When uptake of hydrogen had ceased the solutionwas filtered and the filter cake washed with methanol. The combinedfiltrates were evaporated to dryness under reduced pressure, to givemethyl 3-methyl-4-(2-methoxy-5-aminophenoxy)butyrate as an oil. (317 mg)m/Z 254(M+H).

k) Preparation of the Methyl Ester of2-Anilino-6-(3-[2-methyl-3-carboxypropoxy)-4-methoxy-anilinocarbonylmethoxy)benzoxazole

Methyl 3-methyl-4-(2-methoxy-5-aminophenoxy)butyrate and2-anilino-4-methoxy-6-carboxymethoxybenzoxazole were coupled togetherusing the method described in example 1 g above.

Example 7 Preparation of 2-Anilino-6-(3-[3-carboxypropoxy) Anilinocarbonylmethoxy)benzoxazole

This was prepared by hyrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6) 1.9(m), 2H; 2.38(t), 2H; 3.9-4.0. (m), 5H; 4.7, (s),2H; 6.7-6.8, (m), 2H; 6.9, (d) 1H; 7.0, (t), 1H; 7.2, (d), 2H; 7.3-7.4,(m), 3H; 7.75, (d), 2H; 9.95(s), 1H10.4, (s), 1H; 12.1(brs), 1H. Massspectrum: M+H 492.

a) Preparation of 2-Anilino-4-methoxy-6-carboxymethoxybenzoxazole

This was prepared by the method described in example 6 above.

b) Preparation of methyl-4-(5-aminophenoxy)butyrate

This was prepared by analogous route to that described in example 6above except methyl 4-bromobutyrate was used instead of methyl4-bromo-3-methylbutyrate.2-Anilino-4-methoxy-6-carboxymethoxybenzoxazole andmethyl-4-(5-aminophenoxy)butyrate were coupled together as described inexample 6k.

Example 8 Preparation of 2-Anilino-6-(3-[3-carboxypropoxy]Anilinocarbonylmethyl)-4-methoxybenzoxazole

This was prepared by hyrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.9(m), 2H; 2.35(t), 2H; 3.55(s), 2H; 3.8-4.0(m), 5H;6.6(d)1H; 7.0-7.15(m), 4H; 7.2-7.4, (m), 3H; 7.7, (d), 2H; 10.05(s), 1H;10.5, (s)1H. Mass spectrum: M+H 476.

a) Preparation of 3,5-Difluoro-2-nitrophenol

A solution of 2,4,6-trifluoronitrobenzene (10 g) in dimethylsulphoxide(50 mL) was treated with 10N sodium hydroxide(12 mL) and themixture was stirred at room temperature for 18 h. The mixture wasdiluted with water and washed with ether. The aqueous phase was thenacidified and extracted with ether. The extract was washed with brine,dried and evaporated to dryness and the residue was purified by flashchromatography eluting with increasingly polar mixtures of ethyl acetateand hexane to give the product(8.3 g) [m/e 174, MH−].

b) Preparation of 3,5-Difluoro-2-nitro-anisole

A mixture of 3,5 difluoro-2-nitrophenol(8.3 g), N,N-dimethylformamide(30mL), potassium carbonate(10 g) and iodomethane(5 mL) was stirredvigorously at room temperature for 18 h. The mixture was diluted withwater and extracted with ether. The extract was washed with brine, driedand evaporated to dryness to give the product(8.7 g) as a yellow solid.

c) Preparation of Di-t-butyl 3-fluoro-5-methoxy-4-nitrophenylmalonate

Di-t-butyl malonate(18 g) was added dropwise to a stirred suspension ofsodium hydride[60% dispersion in mineral oil](3.3 g) in N-methylpyrrolidinone(100 mL) under an atmosphere of argon and the mixture wasstirred until effervescence ceased. 3,5 Difluoro-2-nitro-anisole(6.4 g)was added and the mixture was stirred at 80° C. for 2 h. The mixture wascooled to room temperature then partitioned between water and ether andthen the ether extract was dried and evaporated to dryness. The residuewas subjected to flash chromatography eluting with increasingly polarmixtures of ethyl acetate and hexane to give the product(5.5 g)

d) Preparation of Methyl 3-Benzyloxy-5-methoxy-4-nitrophenylacetate

A suspension of di-t-butyl 3-fluoro-5-methoxy-4-nitrophenylmalonate(5.5g) in 1:1 5N hydrochloric acid :acetic acid(15 mL) stirred at reflux for4 h and then evaporated to dryness. The residue was partitioned between2N sodium hydroxide and ether. The aqueous phase was acidified andextracted with ether. The extract was washed with brine, dried andevaporated to dryness. A solution of the residue in benzyl alcohol(15mL) was stirred under argon and treated with sodium hydride,[60%dispersion in mineral oil](1.2 g). The resultant mixture was stirredat 65° C. for 18 h then cooled and partitioned between water and ethylacetate. The aqueous phase was acidfied and extracted with ethyl acetateand the extract dried and evaporated to dryness. A solution of theresidue in methanol(50 mL) was treated with concentrated sulphuricacid(1 mL) and the solution refluxed for 2 h. The cooled solution wasdiluted with water and extracted with ether. The ether extract waswashed with aqueous sodium hydrogen carbonate, brine, dried andevaporated to dryness. The residue then was subjected to flashchromatography eluting with increasingly polar mixtures of ethyl acetateand hexane to give the product(2.85 g). [m/e332, MH+].

e) Preparation of 2-Anilino-4-methoxy-6-methoxycarbonylmethylbenzoxazole

A mixture of methyl 3-benzyloxy-5-methoxy-4-nitrophenylacetate (1.7 g),10% palladium on carbon catalyst(0.2 g), tetrahydrofuran(15 mL) andethanol(15 mL) was stirred under an atmosphere of hydrogen for 18 h. Themixture was filtered and the filtrate treated withphenylisothiocyanate(0.72 g) followed by yellow mercuric oxide(1,55 g).The mixture was stirred at reflux for 2 h, treated with a furtherportion of mercuric oxide (1.55 g) and refluxed for a farther 1 h. Themixture was then filtered and the filtrate was evaporated to dryness.The residue was purified by flash chromatography eluting withincreasingly polar mixtures of ethyl acetate and hexane to give theproduct. [m/e3 1 3, MH+].

f) Preparation of 2-Anilino-4-methoxy-6-carboxylmethyl benzoxazole

2-Anilino4-methoxy-6-methoxycarbonylmethylbenzoxazole was thenhydrolysed by the process described in example 1 to give2-anilino-4-methoxy-6-carboxylmethyl benzoxazole.

Methyl-4-(5-aminophenoxy)butyrate was made as described in example 7above and coupled with 2-anilino-4-methoxy-6-carboxylmethylbenzoxazoleaccording to the method described in example 7 to produce the methylester of 2-anilino-6-(3-[3-carboxypropoxy)anilinocarbonylmethy)-4-methoxybenzoxazole

Example 9 Preparation of2-Anilino-6-{3-[3-carboxypropoxy]anilinocarbonylmethyl} benzothiazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.9(m), 2H; 2.35(t), 2H; 3.7(s), 2H; 3.9, (t), 2H;6.6(d)1H; 7.0, (t)1H; 7.05-7.2, (m), 3H; 7.25-7.4, (m), 4H; 7.5, (d),1H; 7.7-7.8, (m), 3H; 10.1, (s), 1H. Mass spectrum: M+H 462.

a) Preparation of Methyl 3-(4-Methoxybenzylthio)-4-nitrophenylacetate

A mixture of methyl 3-fluoro4-nitrophenylacetate(1.05 g),N-methylpyrrolidinone(10 mL) and 4-methoxybenzyl mercaptan was stirredunder argon and treated with sodium hydride(0.22 g of a 60% dispersionin mineral oil) and the resulting mixture was stirred at ambienttemperature for 0.5 h. Water was added and the mixture was extractedwith ether, and the extract was washed with brine, dried and evaporatedto dryness. The residue was purified by flash chromatography elutingwith increasingly polar mixtures of ethyl acetate and hexane to give theproduct (1.35 g), [m/e365, (M+NH4)⁺].

b) Preparation of Methyl 4-Amino-3-(4-methoxybenzylthio) phenylacetate

A mixture of methyl 3-(4-methoxybenzylthio)-4-nitrophenylacetate(1.2 g),methanol(25 mL), tetrahydrofuran(25 mL), water(10 mL), ammoniumchloride(0.2 g) and iron powder(1 g) was stirred at reflux for twohours. The mixture was cooled, diluted with water and ethyl acetate andfiltered and the organic phase was separated, dried and evaporated todryness to give the product(1. 05 g)[m/e318, MH+].

c) Preparation of Methyl 3-(4-Methoxybenzylthio)-4-(phenylthioureido)phenylacetate

A mixture of methyl 4-amino-3-(4-methoxybenzylthio) phenylacetate(0.8g), acetonitrile(5 mL) and phenylisothiocyanate(0.34 g) was stirred at60° C. for 18 hr. The mixture was evaporated to dryness and the residuewas purified by flash chromatography eluting with increasingly polarmixtures of ethyl acetate and hexane to give the product (0.42 g),[m/e453, MH+].

d) Preparation of 2-Anilino-6-methoxycarbonylmethyl benzothiazole

A mixture of methyl 3-(4-methoxybenzylthio)-4-(phenylthioureido)phenylacetate(0.42 g), trifluoroacetic acid(5 mL) and yellow mercuricoxide(0.3 g) was stirred at 70° C. for 1 hr, cooled to ambienttemperature and treated with water and ethyl acetate. The organic phasewas separated and washed successively with water, aqueous sodiumhydrogen carbonate and brine. The extract was dried evaporated todryness and the residue was purified by flash chromatography elutingwith increasingly polar mixtures of ethyl acetate and hexane to give theproduct. (0.25 g), [m/e299, MH+].

e) Preparation of 2-Anilino-6-carboxymethylbenzothiazole

2-Anilino-6-methoxycarbonylmethyl benzothiazole was hydrolysed by theprocess described in example 1 to give2-anilino-6-carboxymethylbenzothiazole [m/e283, MH−].

Methyl4-(5-aminophenoxy)butyrate was made as described in example 7above and coupled with 2-anilino-6-carboxymethylbenzothiazole accordingto the method described in example 7 to produce the methyl ester of2-anilino-6-{3-[3-carboxypropoxy]anilino carbonyl methyl}benzothiazole

Example 10 Preparation of 2-Anilino-6-{3-[3-carboxypropoxy](N-methylanilino) carbonylmethyl}benzoxazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.9(m), 2H; 2.35(t), 2H; 3.15, (s)3H; 3.7(m), 2H;3.95(t), 2H; 6.8-7.05, (m)4H7.1, (m), H; 7.25-7.4, (m), m4H; 7.75, (d),2H; 10.5(s), 1 H. Mass spectrum: M+H 460.

a) Preparation of 2-Anilino-6-carboxymethylbenzoxazole

This is described in example 1 above.

b) Preparation of Methyl 4-(3-t-Butoxycarbonylaminophenoxy)butyrate

A mixture of methyl 4-(3-aminophenoxy)butyrate(0.42 g),tetrahydrofuran(5 mL) and di-t-butyl dicarbonate(0.44 g) was stirred at60-70° C. for 18 h. The mixture was evaporated to dryness and theresidue was then purified by flash chromatography eluting withincreasingly polar mixtures of ethyl acetate and hexane to give theproduct (0.6 g), [m/e310,MH+].

c) Preparation of Methyl 4-(3-t-Butoxyearbonyl-[N-methyl]amino phenoxy)butyrate

A mixture of sodium hydride[60% dispersion in mineral oil](0.04 g),iodomethane (0.2 mL) and N-,methyl pyrrolidinone(100 mL) was stirredunder an atmosphere of argon and treated with methyl4-(3-t-butoxycarbonylaminophenoxy)butyrate(0.2 g). The mixture wasstirred at ambient temperature for 0.5 h, treated with water and thenextracted with ether. The ether extract was washed successively withwater and brine, dried and evaporated to dryness to give theproduct(0.21 g), [m/e324, MH+].

d) Preparation of Methyl 4-(N-Methylaminophenoxy)butyrate

A solution of methyl4-(3-t-butoxycarbonyl-[-methyl]aminophenoxy)butyrate(0.2 g) in a mixtureof dichloromethane(1 mL) and trifluoroacetic acid(1 mL) was kept atambient temperature for 1 h and evaporated to dryness. The residue wastreated with water and ethyl acetate and the mixture was stirred whilemaking basic with potassium carbonate. The organic phase was separated,dried and evaporated to dryness to give the product (0.14 g), [m/e224,MH+].

e) Preparation of 2-Anilino-6-{3-[3-methoxyearbonylpropoxy](N-methylanilino)carbonyl methyl}benzoxazole

A mixture of 2-anilino-6-carboxymethylbenzoxazole(0.09 g),dichloromethane(10 mL) and thionyl chloride(0.2 mL) was stirred at roomtemperature for 3 h and then evaporated to dryness. A solution of theresidue in tetrahydrofuran was added to a stirred mixture ofmethy-4-(N-methylaminophenoxy)butyrate(0.07 g), triethylamine(0.1 mL)and tetrahydrofuran(2 mL) and the mixture was stirred at roomtemperature for 18 h. Ethyl acetate(10 mL) was added and the mixturewashed successively with 1N hydrochloric acid, 1N sodium hydroxide andbrine, dried and evaporated to dryness to give product (0.08 g),[m/e474, MH+].

Example 11 Preparation of 2-Anilino-6-(1-(3-[3-carboxypropoxy]anilinocarbonyl)ethyl)benzoxazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.4(d), 3H; 1.9(m), 2H; 2.35(t), 2H; 3.8-3.95(m), 3H;6.8(d), 1H; 7.0(t), 1H; 7.05-Mass spectrum: M+H 460.

a) Preparation of Dimethyl-2-(3-benzyloxy4-nitrophenyl)-2-methylmalonate

A mixture of dimethyl-(3-benzyloxy-4-nitrophenyl)malonate(2.3 g),N-methylpyrrolidinone(15 mL) and a 60% dispersion of sodium hydride inmineral oil(0.31 g) was stirred under an argon atmosphere at 0° C. for0.5 h. The mixture was treated with iodomethane(0.8 mL) and stirred atambient temperature for 4 h then treated with water (50 mL). Theprecipitate was collected and washed with water and hexane to givedimethyl-2-(3-benzyloxy-4-nitrophenyl)-2-methylmalonate(2.19 g).[m/e374(MH+)].

b) Preparation of 2-(3-Benzyloxy-4-nitrophenyl)propionic Acid

A mixture ofdimethyl-2-[(3-benzyloxy-4-nitrophenyl)]-2-methyhalonate(2.16 g),methanol(10 mL), tetrahydrofuran(10 mL) and 2N sodium hydroxide(10 mL)was stirred at ambient temperature for 3 h. The solution was acidifiedwith 2N hydrochloric acid and the mixture was extracted with ether andthe extract washed with brine, dried and evaporated to dryness to give2-(3-benzyloxy-4-nitrophenyl)propionic acid as a tan solid(1.89 g).[m/e319(MNH4+)].

c) Preparation of Methyl-2-(3-Benzyloxy-4-nitrophenyl)propionate

A mixture of 2-(3-benzyloxy4-nitrophenyl)propionic acid(1.89 g),methanol(30 mL) and concentrated sulphuric acid(1 mL) was heated atreflux for 3 h, cooled to ambient temperature and the mixture wasextracted with ether. The extract washed with brine, dried andevaporated to dryness to givemethyl-2-(3-benzyloxy-4-nitrophenyl)propionate(1.8 g). [m/e316(MH+)].

Methyl4-(5-aminophenoxy)butyrate was made as described in example 7above and coupled with methyl-2-(3-benzyloxy-4-nitrophenyl)propionateaccording to the method described in example 7 to produce the methylester of 2-anilino-6-(1-(3-[3-carboxypropoxy]anilinocarbonyl)ethyl)benzoxazole.

Example 12 Preparation of 2-Anilino-6-(2-(3-[3-carboxypropoxy]anilinocarbonyl)prop-2-yl))benzoxazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.6(s), 6H; 1.9(m), 2H; 2.35(t), 2H; 3.9(t), 2H;6.8(d), 1H; 7.0(t), 1H; 7.05-7.2(m), 3H; 7.25(s)1H; 7.3-7.45(m), 3H; 7.5(m)1H; 7.75(d), 2H; 9.0(s), H; 10.55(s), 1H; 12.1(s)1H. Mass spectrum:M+H 474.

a) Preparation of Methyl-2-(3-benzyloxy4-nitrophenyl)propionate

This was prepared according to example 11 above.

b) Preparation ofDimethyl-2-(3-benzyloxy-4-nitrophenyl)-2-methylmalonate

A mixture of methyl-2-(3-benzyloxy4-nitrophenyl)propionate(0.8 g),N-methylpyrrolidinone(5 mL) and a 60% dispersion of sodium hydride inmineral oil(0.19 g) was stirred under an argon atmosphere at 0° C. for0.5 h. The mixture was treated with iodomethane(0.45 mL) and stirred atambient temperature for 1 h then treated with water (50 mL). Theprecipitate was collected and washed with water and hexane to give theproduct (2.19 g). [m/e330(MH+)].

Methyl-4-(5-aminophenoxy)butyrate was made as described in example 7above and coupled withdimethyl-2-(3-benzyloxy-4-nitrophenyl)-2-methylmalonate according to themethod described in example 7 to produce the methyl ester of2-Anilino-6-(2-(3-[3-carboxypropoxy]anilinocarbonyl)prop-2-yl))benzoxazole.

Example 13 Preparation of2-(3-Pyridylamino)-6-{3-[3-carboxypropoxy]anilino carbonylmethyl}benzoxazole

This was prepared by hydrolysis of the methyl ester by the processdescribed in example 1.

1H nmr (DMSO d6): 1.9(m), 2H; 2.35(t), 2H; 3.7(s), 2H; 3.9(t), 2H;6.6(d), 1H;7.0-7.5(m), 9H; 8.25(m), 2H; 8.85(s), 1H; 10.08(s),1H. Massspectrum: M+H 447.

a) Preparation of 2-(3-Pyridylamino)-6-carboxymethylbenzoxazole

This is described in example 1 above.

Methyl4-(5-aminophenoxy)butyrate was made as described in example 7above and coupled with 2-(3-pyridylamino)-6-carboxymethylbenzoxazoleaccording to the method described in example 7 to produce the methylester of 2-(3-pyridylamino)-6-{3-[3-carboxypropoxy]anilinocarbonylmethyl}benzoxazole

Example 14

The compounds of the invention or pharmaceutically acceptable saltsthereof may be formulated into tablets together with, for example,lactose Ph.Eur, Croscarmellose sodium, maize starch paste (5% w/v paste)and magnesium stearate for therapeutic or prophylactic use in humans.The tablets may be prepared by conventional procedures well known in thepharmaceutical art and may be film coated with typical coating materialssuch as hydroxypropylmethylcellulose.

In Vitro and In Vivo Assays

The following abbreviations are used. Suitable sources of materials arelisted below.

MOLT-4 cells - human T-lymphoblastic leukaemia cells (EuropeanCollection of Animal Cell Cultures, Porton Down)

Fibronectin—purified from human plasma by gelatin-sepharose affinitychromatography according to the methods described in E.Nengvall,E.Ruoslahti, Int. J. Cancer, 1977, 20, pages 1-5 and J. Forsyth et al,Methods in Enzymology, 1992, 215 pages 311-316).

RPMI 1640—cell culture medium. (Life technologies, Paisley UK).

PBS—Dulbecco's phosphate buffered saline (Life Technologies).

BSA—Bovine serum albumin, fraction V (ICN, Thame, UK).

CFA—Complete Freund's Adjuvant (Life Technologies).

In the following assays and models references to compound(s) refers tothe compounds of formula (I) according to the present invention.

1.1 In Vitro Assay

1.1.1 MOLT-4 cell/Fibronectin Adhesion Assay.

The MOLT-4 cell/fibronectinadhesion assay was used to investigate theinteraction of the integrin α₄-β₁expressed on the MOLT-4 cell membranewith fibronectin. Polystyrene 96 well plates were coated overnight at 4°C. with fibronectin, 100 μl of 10 μg/ml in PBS. Non-specific adhesionsites were blocked by adding 100 μl BSA, 20 mg/ml. After incubating for1 h at room temperature, the solutions were aspirated. MOLT-4 cellssuspended in serum-free RPMI-1640 medium 2E6 cells/ml (50 μl) andsolutions of compound diluted in the same medium (50 μl) were added toeach well. After incubation for 2 h at 37° C. in a humidified atmosphereof 5% (v/v) CO₂, non-adherent cells were removed by gentle shakingfollowed by vacuum aspiration. Adherent cells were quantified by acalorimetric acid phosphatase assay. To each well was added 100 μlp-nitrophenyl phosphate (6 mg/ml) in 50 mM sodium acetate buffer, pH5.0, containing 1% Triton X-100. After incubation for 1 h at 37° C., 50μl sodium hydroxide (1M) was added to each well and the absorbance 405nm was measured on a microplate spectrophotometer. Compounds whichinhibited adhesion gave a lower absorbance reading. Standard, controland test conditions were assayed in triplicate. Percentage inhibitionwas calculated with respect to total (no inhibitor) and non-specific (nofibronectin) standards on each plate.

1.2 In-vivo Inflammation Models

Activity of a compound can be tested in the following models.

15 1.2.1 Ovalbumin Delayed type Hypersensitivity in Mice

Balb/c female mice (20-25 g) are immunised on the flank with an 1:1(v/v) emulsion of ovalbumin (2 mg/ml) with CFA. Seven days later themice are challenged by subplantar injection of 1% heat aggregatedovalbumin in saline (30 μl) into the right hind foot pad. Swelling ofthe foot develops over a 24 hour period following which foot padthickness is measured and compared with the thickness of thecontralateral uninjected foot. The percentage increase in foot padthickness is calculated. Compounds are dosed orally by gavage to groupsof 5 mice at doses ranging from 0.001 mg/kg to 100 mg/kg. Inhibition ofthe inflammatory response is calculated comparing vehicle treatedanimals and compound treated groups.

1.2.2. Collagen-induced Arthritis in Mice

DBA/1 male mice are immunised with 0.1 ml of an emulsion prepared fromequal volumes of bovine collagen type II in 0.05M acetic acid (2 mg/ml)and CFA. This mixture is injected at the base of the tail. Twenty dayslater compounds are dosed orally by gavage at doses ranging from 0.001mg/kg/day to 100 mg/kg/day. On the day following the first dose, eachanimal receives an intra-peritoneal booster injection of 0.1 ml ofcollagen type II in acetic acid. The mice are assessed for the incidenceand severity of arthritis in all four limbs for up to 28 days.Inhibition of arthritis is calculated by comparing vehicle treated andcompound treated mice.

What is claimed is:
 1. A compound of formula (I)

wherein: A is a benzoxazole or benzothiazole, optionally substitutedwith one or more substituents independently selected from C₁₋₆ alkyl,C₁₋₆ alkanoyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₁₋₆ alkoxy, C₁₋₆ alkylamino,C₁₋₆ alkylthio, C₁₋₄ alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆alkylaminoC₁₋₆ alkyl, carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆alkynyloxy, di-[(C₁₋₆)alkyl]amino, C₂₋₆ alkanoylamino, N—C₁₋₆alkylcarbamoyl, C₁₋₆ alkoxylcarbonyl, halogeno, nitro, cyano, aminotrifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl, linked to the nitrogen via a ring carbon atom inone ring and to the group B by a ring carbon atom in the second ring; Bis a linking group connecting group A to group D selected fromacetamido, —C(R^(c)R^(d))—C(O)—NR^(e)—, where R^(c), R^(d) and R^(e) areeach independently selected from hydrogen and C₁₋₂ alkyl, and—O—CH₂—C(O)—NH—; C is phenyl optionally substituted with one or moresubstituents independently selected from C₁₋₆ alkyl, C₂₋₆ alkenyl, C₂₋₆alkynyl, C₁₋₆ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₆ alkylthio,C₁₋₄ alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆ alkylaminoC₁₋₆ alkyl,carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆ alkynyloxy,di-[(C₁₋₆)alkyl]amino, C₂₋₆ alkanoylamino, N—C₁₋₆ alkylcarbarnoyl, C₁₋₆alkoxylcarbonyl, phenoxy, cyano, nitro, amino, halogeno,trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(pO)H where p is 1 or2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl, linked to NR¹ through a ring carbon atom; D isphenyl optionally substituted with one or more substituentsindependently selected from C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆ alkynyl, C₁₋₆alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₆ alkylthio, C₁₋₄alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆ alkylamninoC₁₋₆ alkyl,carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆ alkynyloxy,di-[(C₂₋₆)alkyl]amino, C₁₋₆ alkanoylamino, N—C₁₋₆ alkylcarbamoyl, C₁₋₆alkoxylcarbonyl, phenoxy, cyano, nitro, amino, halogeno,trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl; R¹ is hydrogen, C₁₋₅ alkyl, C₁₋₃ alkanoyl orC₁₋₃ alkoxycarbonyl; R² to R⁵ are each independently selected fromhydrogen, C₁₋₆ alkyl, aryl and heteroaryl containing up to 2 heteroatomschosen from oxygen, sulphur and nitrogen, the aryl and heteroaryloptionally substituted with C₁₋₆ alkyl, C₁₋₆ alkenyl, C₂₋₆ alkynyl, C₁₋₄alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₄ alkylC₁₋₆ alkyoxyl, C₁₋₆alkylaminoC₁₋₆ alkyl, nitro, cyano, halogeno, trifluoromethyl, hydroxy,(CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a), and —CONR^(a)R^(b), whereR^(a) and R^(b) are independently selected from hydrogen and C1-6 alkylor two of R² to R⁵ can be taken together to form a 3 to 7 membered ring;R⁶ is an acidic functional group; r and s are each independently 0 or 1with the proviso that r and s cannot both be 0; or a pharmaceuticallyacceptable salt or in vivo hydrolysable protected acidic functionalgroup thereof.
 2. A compound according to claim 1 wherein A isbenzoxazolyl.
 3. A compound of formula (II)

wherein R¹ is hydrogen, C₁₋₅ alkyl, C₁₋₃ alkanoyl or C₁₋₃alkoxycarbonyl; R² to R⁵ are each independently selected from hydrogen,C₁₋₆ alkyl, aryl and heteroaryl containing up to 2 heteroatoms chosenfrom oxygen, sulphur and nitrogen, the aryl and heteroaryl optionallysubstituted with C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₄ alkoxy, C₁₋₄alkanoyl, C₁₋₆ alkylamino, C₁₋₄alkylC₁₋₆alkyoxyl,C₁₋₆alkylaminoC₁₋₆alkyl, nitro, cyano, halogeno, trifluoromethyl,hydroxy, (CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a), and —CONR^(a)R^(b),where R^(a) and R^(b) are independently selected from hydrogen and C₁₋₆alkyl or two of R² to R⁵ can be taken together to form a 3 to 7 memberedring; each R⁷ is independently selected from C₁₋₆ alkyl, C₂₋₆alkenyl,C₂₋₆alkynyl, C₁₋₄ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino,C₁₋₄alkoxylC₁₋₆alkyl, C₁₋₆alkylaminoC₁₋₆alkyl, cyano, nitro, halogeno,trifluoromethyl, hydroxy, (CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a), and—CONR^(a)R^(b), where R^(a) and R^(b) are independently hydrogen or C₁₋₆alkyl, or two adjacent substituents can be taken together to form a 5-7membered ring; R⁸ to R¹⁴ are independently selected from hydrogen, C₁₋₄alkyl, C₁₋₄ alkanoyl, C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₄ alkoxy,C₁₋₆ alkylamino, C₁₋₄alkoxylC₁₋₆alkyl, C₁₋₆ alkylaminoC₁₋₆alkyl,halogeno, nitro, cyano, trifluoromethyl, hydroxy, (CH₂)_(p)OH where p is1 or 2, —CO₂R^(a), and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently hydrogen or C₁₋₆ alkyl; m is zero or an integer from 1 to5; and r and s are each independently 0 or 1 with the proviso that r ands cannot both be 0; or a pharmaceutically acceptable salt or in vivohydrolysable protected acidic functional group thereof.
 4. A compoundaccording to claim 3 wherein R² and R³ are independently selected fromhydrogen or C₁₋₆ alkyl; R¹, R⁴ and R⁵ are each hydrogen; R⁷ isindependently selected from halogeno and C₁₋₆ alkyl; R⁸, R⁹ to R¹¹ andR¹⁴ are each hydrogen; R¹⁰ is hydrogen or methoxy; R¹² is C₁₋₆ alkoxy,halogeno or hydrogen; s is zero, m is zero, 1 or 2, and r is 1, or apharmaceutically acceptable salt or in vivo hydrolysable protectedacidic functional group thereof.
 5. A pharmaceutical compositioncomprising a compound according to any one of claims 1 to 4, or apharmaceutically acceptable salt or an in vivo hydrolysable protectedacidic functional group thereof in association with a pharmaceuticallyacceptable diluent or carrier.
 6. A method for inhibiting theinteraction between VCAM-1 and/or fibronectin and the intergrin receptorVLA-4 warm-blooded mammals in need of such treatment which comprisesadministering to said warm-blooded mammals an effective amount of acompound according to any one of of claims 1 to 4 or a pharmaceuticallyacceptable salt or an in vivo hydrolysable protected acidic functionalgroup thereof.
 7. A method according to claim 6 for treating multiplesclerosis, rheumatoid arthritis, asthma, coronary artery disease,psoriasis, atherosclerosis, transplant rejection, inflammatory boweldisease, insulin-dependent diabetes and glomerulonephritis.
 8. A processfor preparing a compound of formula (I), a pharmaceutically acceptablesalt or an in vivo hydrolysable protected acidic functional goupthereof,

wherein: A is a benzoxazole or benzothiazole, optionally substitutedwith one or more substituents independently selected from C₁₋₆ alkyl,C₁₋₆ alkanoyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₁₋₆ alkoxy, C₁₋₆ alkylamino,C₁₋₆ alkylthio, C₁₋₄ alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆alkylaminoC₁₋₆ alkyl, carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆alkynyloxy, di-[(C₁₋₆)alkyl]amino, C₂₋₆ alkanoylamino, N—C₁₋₆alkylcarbamoyl, C₁₋₆ alkoxylcarbonyl, halogeno, nitro, cyano, aminotrifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl, linked to the nitrogen via a ring carbon atom inone ring and to the group B by a ring carbon atom in the second ring; Bis selected from acetamido, —C(R^(c)R^(d))—C(O)—NR^(e)—, where R^(c),R^(d) and R^(e) are each independently selected from hydrogen and C₁₋₂alkyl, and —O—CH₂—C(O)—NH—; C is phenyl optionally substituted with oneor more substituents independently selected from C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆ alkynyl, C₁₋₆ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₆alkylthio, C₁₋₄ alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆alkylaminoC₁₋₆ alkyl, carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆alkynyloxy, di-[(C₁₋₆)alkyl]amino, C₂₋₆ alkanoylamino, N—C₁₋₆alkylcarbamoyl, C₁₋₆ alkoxylcarbonyl, phenoxy, cyano, nitro, amino,halogeno, trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH wherep is 1 or 2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) areindependently hydrogen or C₁₋₆ alkyl, linked to NR¹ thrqough a ringcarbon atom; D is phenyl optionally substituted with one or moresubstituents independently selected from C₁₋₆ alkyl, C₂₋₆alkenyl, C₂₋₆alkynyl, C₁₋₆ alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₆ alkylthio,C₁₋₄ alkylsulphonyl, C₁₋₄ alkoxylC₁₋₆ alkyl, C₁₋₆ alkylaminoC₁₋₆ alkyl,carboxy, carbamoyl, C₂₋₆ alkenyloxy, C₂₋₆ alkynyloxy,di-[(C₂₋₆)alkyl]amino, C₁₋₆ alkanoylamino, N—C₁₋₆ alkylcarbamoyl, C₁₋₆alkoxylcarbonyl, phenoxy, cyano, nitro, amino, halogeno,trifluoromethyl, trifluoromethoxy, hydroxy, (CH₂)_(p)OH where p is 1 or2, —CO₂R^(a) and —CONR^(a)R^(b), where R^(a) and R^(b) are independentlyhydrogen or C₁₋₆ alkyl; R¹ is hydrogen, C₁₋₅ alkyl, C₁₋₃ alkanoyl orC₁₋₃ alkoxycarbonyl; R² to R⁵ are each independently selected fromhydrogen, C₁₋₆ alkyl, aryl and heteroaryl containing up to 2 heteroatomschosen from oxygen, sulphur and nitrogen, the aryl and heteroaryloptionally substituted with C₁₋₆ alkyl, C₁₋₆ alkenyl, C₂₋₆ alkynyl, C₁₋₄alkoxy, C₁₋₄ alkanoyl, C₁₋₆ alkylamino, C₁₋₄ alkylC₁₋₆ alkyoxyl, C₁₋₆alkylaminoC₁₋₆ alkyl, nitro, cyano, halogeno, trifluoromethyl, hydroxy,(CH₂)_(p)OH where p is 1 or 2, —CO₂R^(a), and —CONR^(a)R^(b), whereR^(a) and R^(b) are independently selected from hydrogen and C₁₋₆ alkylor two of R² to R⁵ can be taken together to form a 3 to 7 membered ring;R⁶ is an acidic functional group; r and s are each independently 0 or 1with the proviso that r and s cannot both be 0; or a pharmaceuticallyacceptable salt or in vivo hydrolysable protected acidic functionalgroup thereof, which process comprises coupling together, via theformation of an amide bond, a compound of formula (III)

where L is a leaving group, and an amine containing group D, where anyfunctional group is optionally protected; and thereafter, if necessary:a) removing any protecting group; and b) forming a pharmaceuticallyacceptable salt or in vivo hydrolysable protected acidic functionalgroup.